Both original bNK2A-C10C20 and an analog bNK2A-S10S20 peptides displayed strong antimicrobial activities against Histophilus somni.

(A). Two bovine H. somni pneumonic isolates (91 and 2336) were incubated with indicated concentrations of peptides or PBS (control) and incubated at 37°C in a humidified atmosphere of 7.5% CO₂ for 60 min. (B). The original bNK2A-C10C20 peptide (20 μM) was pre-incubated with 0.2, 0.5, and 1.0 mM DTT for 20 min before incubation with H. somni (91 and 2336). Results shown are the means and SD of three independent experiments.